The most common system for tensioning musical drum heads is simply a series of casings around the perimeter of the drum body, either fixed to the drum body itself, or to the opposing casing tensioning the opposite head. Each casing has an internally threaded socket into which a corresponding tension screw is threaded. The other end of the tension screw passes through a corresponding hole in the rigid pressure rim that pulls down on the metal, plastic or wood ring (counterhoop) that forms the perimeter of the head. The tension is generated by simply turning the screws in or out. The problem has always been that for a drum head to vibrate at its maximum, it must have equal tension in every direction. This has been a very slow and laborious process of continuously readjusting the screws until a fair approximation was achieved, and a perfectly balanced tension was rarely met. On drums where rapid pitch changes were to be made, as on timpani, an attempt to balance the tension was made through a floating tension base (as on the original European style Dresden timpani) that pulled on the screws directly, or through a spider linkage (as on William F. Ludwig style timpani). If only two opposing tension screws had been involved, this system would have worked. However because the systems include multiple (at least 6) screw sets, the result was a system that, when any other tension screw was adjusted, it effected all the other screws differently and often only confused the process.
Another problem is that because mechanical linkage is required, the controlling pedal must be in a fixed location on the drum. This at times keeps the pedal from being placed in the most desirable position.
Another design by Saul Goodman, used the typical tension screw means of manually balancing the tension. He then added a small sprocket to each screw and looped a continuous bicycle chain around the drum, engaging each of the individual tension screw sprockets so that all the screws could be turned equally. After initial balance was achieved it could be fairly well maintained. However drum heads have the property of becoming more stretched in the area where they are struck most frequently and one of the drawbacks of this system was that the ratio of the screws had to be frequently brought back into balance. Another problem is that to turn 6 or more tension screws at once, it takes considerable torque. Not only was this more difficult to do with one hand, but it also made the drum unstable with the torque of the single screw. To compensate he used 2 "T" handles instead of one. This allowed the moving of the chain with the hands in an opposed position necessary to keep the drum from moving or tipping over from the high torque required of one screw, but caused another problem. The user must be striking or causing the drum to vibrate by some means to ascertain the exact tension and consequently the pitch that the drum has reached. With two hands occupied in turning the handles, this becomes impossible. The user must alternate between striking the drum and turning the handles.
Another system devised is marketed as "Roto Toms" and has been limited to use on small drum heads. Because of the structure of the system, it has not been installed on any drum shell or timpani kettle. Without the amplification and resonance of a drum body, the vibrations coming from the bottom surface of the head tend to cancel out the vibrations from the top surface of the head leaving the sound thin, similar to a loudspeaker without an enclosure. The system consists of two very rigid rings that oppose each other and are mounted on a threaded rod by means of a rigid spider in the center each of the rings. By turning the entire assembly on the threaded rod, the rings move in relationship to each other, changing the tension applied to the head. At higher tensions, substantial leverage is again required to turn the mechanism. This tension system suffers from the same problems found in all the floating tension base systems. When any one screw is readjusted it moves the floating base, consequently changing the tension at every other screw to a different degree.
One final problem found in all the existing tension systems is that they all involve a lengthy process for changing the head. All the screws must be completely dissembled so the pressure rim can be removed. The head is then replaced, the pressure rim repositioned, the screws reinstalled and everything retightened and rebalanced. This makes it impossible to make any accurate comparison of different heads because by the time the next head is installed and balanced, the qualities of the previous head are impossible to remember exactly and compare.
None of the afore said systems achieves the benefits of this tuning system. That is, an automatic and constant perfect balancing of tension over the entire head, even when any of the individual tension screws are turned in or out. A light effort rapid tuning system that with the use of a small hydraulic hose allows unlimited placement of the adjusting pedal. A rapid process for changing and instantly bringing a newly mounted head into perfect tension balance.